blood for 13, 21, 18, x, y fish testing –post natal Test

FISH stands for Fluorescent in Situ Hybridization, and it is a molecular cytogenetic technique which uses fluorescent probes that bind those chromosomes that have a high degree of sequence complementarity. The test is used to detect the presence or absence of specific DNA sequences.

The test is done to find any abnormalities in the chromosomes X and Y and to find the presence of extra autosomal chromosomes 13, 21, 18. The trisomy (3 copies instead of 2) of the chromosome 21 is usually found in children with Down syndrome and that of 18 and 13 is found in Edwards syndrome and Patau syndrome, respectively. These are the most common autosomal chromosomes that are found in live births, as most of the other cases of abnormal chromosomes may lead to miscarriages.

Around 1 week Hours

The doctor may ask you to get tested if you want to get your new born screened for any of the following syndromes:

Down Syndrome

Edwards Syndrome

Patau Syndrome

Turner Syndrome

Kinefelter Syndrome 

The test may be ordered by your doctor if -

Your previous pregnancy had some chromosomal abnormality

There have been recurrent miscarriages

You have a family history of chromosomal abnormality

The test will find out if your new born has abnormalities in chromosomes 13, 21, 18, X, or Y.

Your doctor will let you know if there is any need to take any precautions before the test.

Specimen type: Serum (Blood Sample) How is the specimen collected: Through venepuncture collection of blood from a vein within the arm